1. Motion in Two Dimensions

2. Section 6.1
Projectile Motion
 How do I separate projectile motion into horizontal
and vertical components?
 How can I utilize kinematic equations to solve
projectile motion problems?

3. Projectile Motion
 Examples?

4. Path
 Path?
 Trajectory – the path of a object experiencing
projectile motion

5. Projectile Motion
 Projectile – an object shot through the air
 Can be anything
 Kinematic Equations apply
 While the projectile is traveling we can draw a free
body diagram

6. Free – Body Diagram

7. From a cliff…
 If I drop a ball off a cliff, what is the force acting on it?
 What if I push it off the cliff?
 What if I shoot it up at an angle off the cliff?

8. Gravity!
 Gravity is the only acceleration in projectile motion
problems
 Does gravity apply horizontally?
 Is there any acceleration in the horizontal direction?
 Application to equations?

9. Trajectories of Two Softballs
Total Time?

10. Free–Body Diagrams

11. Strategies
 List Data by Horizontal and Vertical
 What is the initial horizontal velocity?
 What is the initial vertical velocity?
 Is there a launch angle?
 What is the launch height?
 What is the launch length?

12. Velocity Components
What if Vx = 8 m/s and Vy = 10 m/s?

13. Examples
 A bowling ball is rolled off a 50 m high cliff with a
velocity of 5 m/s.
 How long does it take the ball to reach the ground?
 How far from the base of the cliff does the ball hit the
ground?
 What are the horizontal and vertical components of
the velocity just before it hits the ground?

14. Homework
 Page 150, # 1 – 3
 Tossed Ball Worksheet

15. Firing a Cannonball
 http://phet.colorado.edu/sims/projectile-
motion/projectile-motion_en.html

16. Short Cuts


17. Example
 A ball is launched at 4.5 m/s at 66° above the
horizontal. What are the maximum height and flight
time of the ball?

18. Homework
 Projectile Motion Worksheet